1. Field of the Invention
Systems consistent with the present invention relate to a concurrent mode antenna system, and more particularly to a concurrent mode antenna system enabling various wireless communication services by transmitting and receiving radio signals of a plurality of frequency bands on a single antenna.
2. Description of the Related Art
With advances of radio communication technology, various radio communication services available using wireless terminals such as mobile phones, personal digital assistants (PDAs), persona computers, and notebook computers are under development, for example, Global System for Mobile communication (GSM), Personal Communication Services (PCS), World Interoperability for Microwave Access (WiMAX), Wireless Local Area Network (WLAN), Wireless Broadband Internet (WiBro), Bluetooth, etc.
The GSM service uses a 890˜960 MHz band, the PCS service uses a 1.8 GHz band, and the WiMAX service uses a 3.6˜3.8 GHz band. The WLAN service uses a 2.4 GHz band according to the Industrial, Scientific & Medical (ISM) band in IEEE 802.11b, and a 5 GHz band according to the Unlicensed National Information Infrastructure (UNII) in IEEE 802.11a. The WiBro service uses a 2.3 GHz band and the Bluetooth service uses 2.4 GHz band.
To use radio communication services using a single wireless terminal over the various frequency bands, the related art employs a multiband antenna system as shown in FIG. 1.
The related art multiband antenna system in FIG. 1 includes a plurality of antennas 110, a plurality of band pass filters (BPFs) 120, and a plurality of radio frequency (RF) circuits 130. The antennas 110 transmit and receive signals of different frequency bands. The BPFs 120 filter the signals transmitted and received on the antennas 110 according to the intended frequency bands.
The related art antenna system of FIG. 1 is subject to a size increase because of using the antennas 110 and the BPFs 120.
To address this problem, a reconfigurable antenna system is being developed not only to receive various wireless communication services on a single antenna but also to use various services at the same time.